Vehicle-to-grid (V2G) — the concept of using vehicle batteries as a source of energy storage and vehicle operating systems as a means of managing that storage — is the banner idea for a larger and more complex set of challenges involving plug-in vehicles and grid operations. Resolving those challenges will complete and streamline the interactions of plug-in vehicles and the power system. Gage’s new venture, EV Grid, will take up those challenges.
After having built electric drivetrains at ACP since 1992 and worked on everything from the EV1 to the Tesla, Gage left the company he co-founded last fall. ACP will “focus on drive system development and, specifically, on Chinese markets,” Gage said, while EV Grid will take up efforts on “battery work, vehicle integration, and fleet testing,” which, he said, are viable programs with “customers waiting for them.”
For EV Grid, “the big commercialization opportunity,” Gage explained, is “vehicle-grid integration,” because “everybody knows if ten people on the block go out and buy a LEAF and they all plug it in at 6 p.m. when they get home, they’re going to have a problem.” Many see this as a liability, Gage said, “but if you manage it properly, it becomes an asset.”
There are, Gage said, communications, control technologies, batteries and high power electronics in BEVs, and “you already have or will soon have high-power connections between the vehicle and the grid.” Using these tools effectively will enhance grid stability. “You want to be able to control them in a way that benefits the grid to the greatest extent,” Gage said, “and the vehicle owner to the greatest extent.”
Many say it is unrealistic to expect the grid to manage the amount of data required for V2G and not feasible to affordably deploy such systems.
But, Gage said, battery technology has advanced so rapidly that even those who doubt V2G “agree the potential for having storage on the grid is very real and very significant.”
There are three ways, Gage explained, to use batteries as grid storage. “One is a big warehouse or trailer truck full of batteries” that is “under the control of a utility or power provider.”
Another, he said, “is the batteries’ second use idea.” When, after eight to ten years of use, BEV batteries with as much as 70 percent to 80 percent of their storage capacity left, are replaced, they could, Gage noted, be gathered and used as grid storage “before they’re ultimately recycled.”
Large centralized battery storage is already being used and more advanced battery technologies are being tested. “Battery second use is not so far along,” Gage said. “Very few, if any, EV batteries have been out there long enough.”
Large-scale implementation of either concept, he said, would be “very costly.”
“The third alternative,” he said, “is vehicle-to-grid.” It is “really doing the same thing,” he explained, except that “you’re extracting two value streams from the battery concurrently, one when the car is being driven and the other when the vehicle is parked and plugged in and the battery is on call to the grid.”
In theory, Gage said, “the capital costs of this approach are much much smaller, probably factors of ten smaller.”
But, he added, “the question is whether you extract enough value from the battery while it’s still good in the car to make everybody happy and not leave the guy in the car either stranded with a dead battery or a worn-out battery.”
The advantage to the driver, theoretically, is “he doesn’t have to pay as much for his battery if somebody else is using it, too.”
Business models, Gage said, are being developed. “Whether the guy gets a check every month or whether he leases his battery at a preferred rate because somebody else is leasing it at the same time,” he explained, “the fundamental economic assumption is that the battery creates two revenue streams,” which “reduces the cost of the primary function, which is transportation.”
EV Grid, will, Gage said, announce a vehicle grid demonstration project in May in conjunction with the University of Delaware and NRG Energy that will include V2G trials and test business models.
A BEV owner, Gage said, might be obligated to make the battery available to the grid or could get a cost-per-month reduction for time plugged in. But any business model must respect the stipulation that “the driver’s needs and wants have priority in all cases.” The driver may earn less, Gage said, but should never be “required to do anything that he thinks might cause him inconvenience or harm.”
V2G doubters, Gage noted, “say it’s way off in the future, and they’re correct,” because “you can’t have V2G without the V. It will certainly not happen any faster than EVs hit the road. But there’s an interactive effect. If V2G works,” he said, “it will hasten the acceptance of EVs by making them look more economical.”